Ok well I dunno!!!

No way of knowing for sure. It is a guess from beginning to end. you can start by last period

That's bin awhile dont know if i remember

Go by your last period.

Ok well I had one at 5 weeks!! And that's the last I was at a doc!!! But I think its arnd 12-13 but I dont know!!!!!!

For 100% certain, birth, lol. But around 20 weeks is when ultrasound is most accurate